1. Field of the Invention
The present invention relates to a manufacturing method of a display device and a display device.
2. Description of the Related Art
Recent years, a display device such as an organic EL display device using an organic EL (Electro-Luminescent) element and a liquid crystal display device has been put into practical use. However, an organic EL element is susceptible to moisture, and therefore there is a fear that an organic EL element deteriorates due to moisture and a lighting defect such as a dark spot is generated. Further, on a liquid crystal display device as well, a problem arises that a characteristics of a thin film transistor changes influenced by moisture that has infiltrated therein, and a display quality deterioration occurs. Therefore, a display device needs to be sealed off in order to prevent a infiltration of moisture and the like into the display device.
However, if a foreign substance is mixed into a sealing film during its formation, there is a fear that a defect is generated on the sealing film, and a display quality deteriorates due to moisture or the like that has infiltrated therein from the defect. Therefore, Japanese Patent Application Laid-Open No. 2015-176717, for example, discloses forming a sealing film with high coverage rate as to a foreign substance by using the ALD (Atomic Layer Deposition) method with which molecules are deposited layer by layer and a very thin sealing film is isotropically formed to form a sealing film.
Further, for example, Japanese Patent Application Laid-Open No. 2007-250370 discloses providing, in advance when a sealing film is laminated, a foreign substance covering part and a bend smoothing part at a bend such as a substance that exists on a surface that forms a sealing film and a border between a horizontal surface and an inclined surface to smooth roughness and a bend, and as a result preventing a defect generation on a sealing film formed thereon.